Apheresis is a technical term describing a medical procedure whereby components of blood are selectively removed from an individual either for the purpose of donation of for treatment. Both cell and plasma donations are made in this way with the cells used for treatment of granulocytopenia, thrombocytopenia and, more recently autologous lymphocytes have been activated ex vivo and used in the treatment of certain malignancies. Therapeutic plasma exchange involving the removal of toxic compounds from the plasma of afflicted individuals now has wide application in the treatment of many diseases with particular application in the areas of rheumatology, neurology, hematology, nephrology and immunology. In Canada, one of the few countries with available national statistics, over 5,000 therapeutic apheresis procedures and 45,000 collection procedures are done each year. Concomitantly, more than 50,000 plasma exchange procedures would be predicted for the United States with ten times the population. The international development of apheresis technology has occurred rapidly over the past 10 years and is now considered to be an essential part of modern medical practice. While the technique has been adapted as a life threatening modality in a number of diseases, there still remains a great deal of definition of application to be done. Clinical trials are currently underway in a number of countries to study the different diseases treated by apheresis and an effort is being made, on an international scale, to share data from these various trials. Recently, the American Society for Apheresis (ASFA) has issued guidelines one the application of this expensive technology. The sharing of data on the progress of clinical trials and of the new developments in apheresis which include extracorporeal absorption techniques for treatment of such diseases as hypercholesterolemia, will greatly assist in the optimal application of this new technology. Since practioners of apheresis are drawn from many specialty areas, there is a need for an international forum in which they can meet to discuss topics of interest. The World Apheresis Association 2nd International Meeting will therefore provide n opportunity for European, Asian and American investigators to meet and share their experiences in apheresis.